The invention relates generally to connectors or adapters, and more particularly to connectors or adapters used to provide video signals from one unit to another unit.
Video signal providing devices, such as graphics accelerators, desktop computers, laptop computers and any other suitable devices may provide video signals that may be output to differing types of monitors or display devices. For example, a personal computer or laptop device may be able to drive a VGA monitor having different resolutions and refresh rates and other types of monitors. Differing monitor manufacturers have differing resolutions and accordingly, graphics accelerators and other video signal providers attempt to provide the proper video signaling to the monitor depending upon the monitor type.
To allow a video signal provider to configure for a number of different monitor types, an industry standard has been adopted to provide a display data channel (DDC) which is a two wire interface that uses I2C protocol to identify monitors. For example, a graphics processor through the DDC wires will send a display configuration request to a monitor using I2C protocol to find out the proper configuration necessary for that monitor, immediately upon boot up of the video signal provider. As a result, a user is presented with a proper display upon power up of a personal computer, for example. Typically, conventional video signal providers default to a VGA type monitor and provide 680 by 480p resolution. Moreover, the output may be in RGB format whereas for high definition televisions and other component video input televisions, such as SDTVs, such devices typically require a component video signal format such as Y, Pr, Pb format. Computer monitors are equipped with a microprocessor or other suitable interface circuit to respond to a display monitor identification request via the DDC wires.
A problem arises with component video input televisions such as HDTVs and SDTVs that do not have a monitor identification system, such as a DDC wiring scheme. Conventional VGA outputs are not suitable for component video input televisions. VGA may be considered a non-component video input television display mode. Accordingly, the conventional video signal providers that can connect to differing types of monitors usually have a default display mode of a non-component video input television type. Accordingly, when a conventional video signal provider is connected to an HDTV through a PC, the video signal provider defaults to an RGB 640 by 480p or other mode and not to the required Y, Pr, Pb 480I, 480p, 720p 1080I or 1080p standard recognized by an SDTV or HDTV. Accordingly, the image display upon power up can be unsuitable It is also known that an SDTV or HDTV may provide a graphic user interface to allow a user to select differing display resolutions. It is also known in wide screen signaling standards, such as the European standard, to require a user to enter a TV model via a graphic user interface. The model type then indicates which type of control information is sent to the TV to alter the television aspect ratio or scan rate if the television is a wide screen, for example. However, such systems typically require a user to enter TV model information and also do not typically interface with video signal providers that provide video signals for differing formats of video signals. Moreover, SDTV""s or HDTVs may support multiple scan rates and do not typically communicate this information over a communication link automatically. Accordingly, with video signal providers that attempt to connect to HDTVs, such video signal providers do not know what TV monitor type that is being connected and do not know the TV monitor capabilities so that the display upon power up is unsuitable. Upon booting up, a conventional laptop computer, graphics accelerator, or any other suitable video signal providing device automatically assumes that the monitor is a VGA type. However, many SDTVs and HDTVs do not support the RGB color space format. Accordingly, the non-component video input television display mode being used outputs, for example, horizontal synchronization pulses and vertical synchronization pulses on pins that are not connectable to the HDTV or SDTV.
In addition, it is known to have VGA to SDTV or HDTV connector boxes that perform (at least one of) color space conversions and timing to convert video signals from VGA (RGB) color space to SDTV or HDTV (Y, Pb, Pr) color space. However, such converter boxes typically duplicate the functions of graphics accelerators and other video signaling providers that perform the color space conversion outside of the converter boxes and can be quite costly.
Accordingly, a need exists for an adapter and method to facilitate an interconnect between a video providing unit having a non-component video input television default display mode, and a component video input television.